Expanding drill-blade



' A'rniv'r tries,

UNITED S'rArE-e TOLLEF HERBERG, OF IIENDRUM, MINNESOTA.

EXPANDING DRlLL-BLADE.

SPECIFICATION forming part of Letters Patent No. 414,411, dated November5, 1889.

Application filed March 27, 1889. Serial No. 304,974. (No model.)

To a/ZZ whom it may cmwern: end of the latch is projected normally out-Be it known that I, TOLLEF UE'RBERG, a Ward, so that its lower end Willbe held in citizen of the United States, residing at Henengagement withthe drill-blades bya spring 55 drum, in the county of Norman and Stateof Q, arranged in the recess L and bearing Minnesota, have invented anew and useful against the latch. The upper end of the ExpandingDrill-Blade, of which the followlatch is of a convex form, as shown inthe flg iS a Specification. drawings, so that it Will be casily operatedby My invention relates to improvenients in the lower end of the casing,as will be pres- 6o cxpanding drill-blades; and it consists in cerentlymore particularly described. Io tain novel features hereinafterdescribed and The construction and arrangement of the claimed. parts ofmy device being thus made known, In the accompan'ying drawings, Figure lis the operation of the same will, it is thought, a side view of myimproved device. Fig. 2 is be readily understood. 65

a vertical section of the same. Fig. 3 is a lVhen the device is to belowered to the horizontal section. Fg. is a perspective bottom of awellor other opening, the latch is view of one of the blades. disengagedfrom the drill-blades, so as to al- Referring to the drawings by letter,A deslow the same to drop by reason of their weight. ignates thedrill-rod, which may be either The ribs and grooves will direct thedrill- 7o solid or tubular, aspreferred, and has its blades inward, sothat they will occupy less 2o lower end bifurcated, thereby providingthe room, and consequently can be easily passed arms B, and through thesaid arms I form a downward through the casing to the bottom horizontalperforation O, as shown. On their of the well, while the pin l preventsthe blades inner opposing sides the arms B are provided falling from thedrill-rod. The device is then 7 5 With the reversely-inclined shouldersD, and lowered in the casing, and when the drillat the base of saidshoulders with the grooves blades strike the bottom of the well theywill E, which extend the entire length of said be forced upward, and byreason of the inclishoulders and follow the Outline thereof. n-ation ofthe grooves and ribs will be directed IThe drill-blades F are inountedbetween the outward and expanded. The drill-blades will 8o arms B, andare provided with the inclined be held in their expanded position by the3o ribs G on their sides, at their upper ends, latoh automaticallyengagingthe notches in adapted to engage the grooves E and slide theirupper ends, as Will be readilyY undertherein. The drill-blades arefurther prostood. Then the drilling has been completed vided with theinclined slots H near their upthe drill is lifted from the well and theblades 85 per ends, and the pin I, secured in the openwill be throwninward, so as to pass easily up ings C in the drill-rod, passes throughthe the casing in the following manner: As the said slot-s. drill-rod israised, the convex end of the latch The drill-blades are provided ontheir outer will be brought against the end of the casing, sides withthe projeotions J, having the aband Will be thereby pressed inward, andthe 9o rupt shoulders K at their upper ends adapted lower end of thelatch is thereby withdrawn 4o to engage with the lower end of thedrill-rod from engagement with the drill-blades, so and thereby limitthe upward movement of that the same Will be free to move. The theblades, and the lower ends of the blades blades after being releasedhave a tendency and of the offsets J are sharpened, so that as to fallby reason of their weight, and this 95 the drill-rod is' rotated theblades will cut the tendency Will be accelerated by the upper ground, aswill be readily understood. ends of the blades striking against the endof The drill-rod is provided in its outer side, 'the casing as thedrill-rod is raised. The near its lower end, with areeess L, and alatchblades will thus be thrown inward and Will M is pivotally secured insaid recess and has pass easily through the casing. Ioo its lower endbent inward to form a hook N, It will be seen from the fore-goingdescripwhich projects through an opening O in the tion that I haveprovided a very simple and drill-rod to engage a notch or notches P inthe efficient drill in which the blades will be seupper ends of thedrill-blades. The upper curely locked in their expanded position, so

as to cut a large opening, and will be automatically released from theirexpanded position When the device is raised. The several parts of thedevice are all protected against injury and are simple in theirconstruction.

Havng thus described my invention,what I claim, and desire to secure byLetters Patent, 1s-

l. The combination, With the drill-rod, of the drill-blades mountedtherein' and provided on their outer sides With the offsets J, havingthe abrupt shoulders K, adapted to impinge against the end of thedrill-rod, and a latch mounted on the drill-rod and adapted to engagethe drill-blades, as set forth.

2. The combination of the drill-rod provided at its loWer end With thearms B, having the transverse perforations C and 'the' inelined groovesE in their inner faces, the drill-blades arranged between the arms B andprovided with the nolined slots H, and the inclined ribs G, engaging thegrooves E,

the pin inserted through the perforations 0,'

4presence of two Witnesses.

TOLLEF HERBERG. WVitnesses:

A. L. GERNON, THoMAs PEDERsoN.

